In electrically driven vehicles, in particular watercraft, battery systems having a multiplicity of electrically interconnected secondary battery cells are used, in particular in order to supply electrical drive mechanisms of the vehicles with electrical energy. For this purpose, a secondary battery, which is formed from the secondary battery cells, of a battery system is situated in a compartment on a vehicle, which is provided for said secondary battery.
As is found, e.g., in the publication “Tentative Rules for Battery Power”, DNV Chips/Highspeed, Light Craft and Navels Surface Craft, Part 6, Chapter 28, considerations are made with respect to the design of battery compartments of watercraft. Such considerations relate to the safety of the crew, the watercraft, and the passengers, and are regularly documented in a hazard assessment which includes multiple steps, such as, e.g., ascertaining hazards and evaluating risks with respect to a battery compartment.
Corresponding considerations have also been made in the automotive sector, as is described, e.g., in CN 102593400 A which describes a system for a secondary battery, according to which the secondary battery can be installed in a vehicle in such a way that the secondary battery is easily accessed for maintenance.
Further considerations have also been made in the field of large battery packs for electric power storage facilities, as shown, e.g., in JP 2009 277394 A. According to these considerations, battery housings are used and are designed in such a way that secondary battery cells situated in the battery housings are accessible in order to be maintained, wherein the battery housings also have suitable properties of thermal radiation.
WO 2011/065639 A1 discloses a battery pack which is intended to allow for simple installation and manufacturing of a battery by providing a row of battery compartments, into which complete secondary batteries or secondary battery cells can be inserted.
Making a repair to battery systems can be difficult in watercraft, in particular, since, due to the limitations of a physical design of a watercraft, some battery cells of a secondary battery or subunits of the secondary battery formed from battery cells are very likely located in areas of a battery compartment of the watercraft which are difficult for maintenance personnel to access. Other battery cells or subunits of the secondary battery can be located in more easily accessed areas of the battery compartment, however.
In a marine environment, the accessibility and the maintenance of a battery system is associated with a number of specific difficulties which are due, inter alia, to the particular size of a battery system which can include twelve or more subunits, the required long service life of the battery system, the requirement that a number of operating requirements be satisfied, many of which can exceed recommended operating limits of a battery system for an optimal service life and power, e.g., in a hazard situation of a watercraft, and the site of a battery system in the watercraft, which can be located in hard-to-access areas of the watercraft.